TL;DR
- Wobble from Mars could be a sign of dark matter
- Gargantuan black hole jets are the biggest seen yet
- Magnifying deep space through the ‘carousel lens’
- Volcanoes may help reveal interior heat on Jupiter's moon
- Organic matter on Mars was formed from atmospheric formaldehyde
Space industry in numbers
The global smart space market size is projected to grow from USD 9.4 billion in 2020 to USD 15.3 billion by 2025, at a Compound Annual Growth Rate (CAGR) of 10.2% during the forecast period. The increasing venture capital funding and growing investments in smart space technology to drive market growth.
Analysts at Morgan Stanley and Goldman Sachs have predicted that economic activity in space will become a multi-trillion-dollar market in the coming decades. Morgan Stanley’s Space Team estimates that the roughly USD 350 billion global space industry could surge to over USD 1 trillion by 2040.
Latest Research
Close encounters of the primordial kind: A new observable for primordial black holes as dark matter
by Tung X. Tran, Sarah R. Geller, Benjamin V. Lehmann, David I. Kaiser in Physical Review D
In a new study, MIT physicists propose that if most of the dark matter in the universe is made up of microscopic primordial black holes — an idea first proposed in the 1970s — then these gravitational dwarfs should zoom through our solar system at least once per decade. A flyby like this, the researchers predict, would introduce a wobble into Mars’ orbit, to a degree that today’s technology could actually detect.
Such a detection could lend support to the idea that primordial black holes are a primary source of dark matter throughout the universe.
“Given decades of precision telemetry, scientists know the distance between Earth and Mars to an accuracy of about 10 centimeters,” says study author David Kaiser, professor of physics and the Germeshausen Professor of the History of Science at MIT. “We’re taking advantage of this highly instrumented region of space to try and look for a small effect. If we see it, that would count as a real reason to keep pursuing this delightful idea that all of dark matter consists of black holes that were spawned in less than a second after the Big Bang and have been streaming around the universe for 14 billion years.”
The study’s co-authors are lead author Tung Tran ’24, who is now a graduate student at Stanford University; Sarah Geller ’12, SM ’17, PhD ’23, who is now a postdoc at the University of California at Santa Cruz; and MIT Pappalardo Fellow Benjamin Lehmann.
Less than 20 percent of all physical matter is made from visible stuff, from stars and planets, to the kitchen sink. The rest is composed of dark matter, a hypothetical form of matter that is invisible across the entire electromagnetic spectrum yet is thought to pervade the universe and exert a gravitational force large enough to affect the motion of stars and galaxies.
Physicists have erected detectors on Earth to try and spot dark matter and pin down its properties. For the most part, these experiments assume that dark matter exists as a form of exotic particle that might scatter and decay into observable particles as it passes through a given experiment. But so far, such particle-based searches have come up empty.
In recent years, another possibility, first introduced in the 1970s, has regained traction: Rather than taking on a particle form, dark matter could exist as microscopic, primordial black holes that formed in the first moments following the Big Bang. Unlike the astrophysical black holes that form from the collapse of old stars, primordial black holes would have formed from the collapse of dense pockets of gas in the very early universe and would have scattered across the cosmos as the universe expanded and cooled.
These primordial black holes would have collapsed an enormous amount of mass into a tiny space. The majority of these primordial black holes could be as small as a single atom and as heavy as the largest asteroids. It would be conceivable, then, that such tiny giants could exert a gravitational force that could explain at least a portion of dark matter. For the MIT team, this possibility raised an initially frivolous question.
“I think someone asked me what would happen if a primordial black hole passed through a human body,” recalls Tung, who did a quick pencil-and-paper calculation to find that if such a black hole zinged within 1 meter of a person, the force of the black hole would push the person 6 meters, or about 20 feet away in a single second. Tung also found that the odds were astronomically unlikely that a primordial black hole would pass anywhere near a person on Earth.
Their interest piqued, the researchers took Tung’s calculations a step further, to estimate how a black hole flyby might affect much larger bodies such as the Earth and the moon.
“We extrapolated to see what would happen if a black hole flew by Earth and caused the moon to wobble by a little bit,” Tung says. “The numbers we got were not very clear. There are many other dynamics in the solar system that could act as some sort of friction to cause the wobble to dampen out.”
To get a clearer picture, the team generated a relatively simple simulation of the solar system that incorporates the orbits and gravitational interactions between all the planets, and some of the largest moons.
“State-of-the-art simulations of the solar system include more than a million objects, each of which has a tiny residual effect,” Lehmann notes. “But even modeling two dozen objects in a careful simulation, we could see there was a real effect that we could dig into.”
The team worked out the rate at which a primordial black hole should pass through the solar system, based on the amount of dark matter that is estimated to reside in a given region of space and the mass of a passing black hole, which in this case, they assumed to be as massive as the largest asteroids in the solar system, consistent with other astrophysical constraints.
“Primordial black holes do not live in the solar system. Rather, they’re streaming through the universe, doing their own thing,” says co-author Sarah Geller. “And the probability is, they’re going through the inner solar system at some angle once every 10 years or so.”
Given this rate, the researchers simulated various asteroid-mass black holes flying through the solar system, from various angles, and at velocities of about 150 miles per second. (The directions and speeds come from other studies of the distribution of dark matter throughout our galaxy.) They zeroed in on those flybys that appeared to be “close encounters,” or instances that caused some sort of effect in surrounding objects. They quickly found that any effect in the Earth or the moon was too uncertain to pin to a particular black hole. But Mars seemed to offer a clearer picture.
The researchers found that if a primordial black hole were to pass within a few hundred million miles of Mars, the encounter would set off a “wobble,” or a slight deviation in Mars’ orbit. Within a few years of such an encounter, Mars’ orbit should shift by about a meter — an incredibly small wobble, given the planet is more than 140 million miles from Earth. And yet, this wobble could be detected by the various high-precision instruments that are monitoring Mars today.
If such a wobble were detected in the next couple of decades, the researchers acknowledge there would still be much work needed to confirm that the push came from a passing black hole rather than a run-of-the-mill asteroid.
“We need as much clarity as we can of the expected backgrounds, such as the typical speeds and distributions of boring space rocks, versus these primordial black holes,” Kaiser notes. “Luckily for us, astronomers have been tracking ordinary space rocks for decades as they have flown through our solar system, so we could calculate typical properties of their trajectories and begin to compare them with the very different types of paths and speeds that primordial black holes should follow.”
To help with this, the researchers are exploring the possibility of a new collaboration with a group that has extensive expertise simulating many more objects in the solar system.
“We are now working to simulate a huge number of objects, from planets to moons and rocks, and how they’re all moving over long time scales,” Geller says. “We want to inject close encounter scenarios, and look at their effects with higher precision.”
Black hole jets on the scale of the cosmic web
by Martijn S. S. L. Oei, Martin J. Hardcastle, Roland Timmerman, Aivin R. D. J. G. I. B. Gast, Andrea Botteon, Antonio C. Rodriguez, Daniel Stern, Gabriela Calistro Rivera, Reinout J. van Weeren, Huub J. A. Röttgering, Huib T. Intema, Francesco de Gasperin, S. G. Djorgovski in Nature
Astronomers have spotted the biggest pair of black hole jets ever seen, spanning 23 million light-years in total length. That’s equivalent to lining up 140 Milky Way galaxies back to back.
“This pair is not just the size of a solar system, or a Milky Way; we are talking about 140 Milky Way diameters in total,” says Martijn Oei, a Caltech postdoctoral scholar and lead author of a new paper reporting the findings. “The Milky Way would be a little dot in these two giant eruptions.”
The jet megastructure, nicknamed Porphyrion after a giant in Greek mythology, dates to a time when our universe was 6.3 billion years old, or less than half its present age of 13.8 billion years. These fierce outflows — with a total power output equivalent to trillions of suns — shoot out from above and below a supermassive black hole at the heart of a remote galaxy.
Prior to Porphyrion’s discovery, the largest confirmed jet system was Alcyoneus, also named after a giant in Greek mythology. Alcyoneus, which was discovered in 2022 by the same team that found Porphyrion, spans the equivalent of around 100 Milky Ways. For comparison, the well-known Centaurus A jets, the closest major jet system to Earth, spans 10 Milky Ways.
The latest finding suggests that these giant jet systems may have had a larger influence on the formation of galaxies in the young universe than previously believed. Porphyrion existed during an early epoch when the wispy filaments that connect and feed galaxies, known as the cosmic web, were closer together than they are now. That means enormous jets like Porphyrion reached across a greater portion of the cosmic web compared to jets in the local universe.
“Astronomers believe that galaxies and their central black holes co-evolve, and one key aspect of this is that jets can spread huge amounts of energy that affect the growth of their host galaxies and other galaxies near them,” says co-author George Djorgovski, professor of astronomy and data science at Caltech. “This discovery shows that their effects can extend much farther out than we thought.”
The Porphyrion jet system is the biggest found so far during a sky survey that has revealed a shocking number of the faint megastructures: more than 10,000. This massive population of gargantuan jets was found using Europe’s LOFAR (LOw Frequency ARray) radio telescope.
While hundreds of large jet systems were known before the LOFAR observations, they were thought to be rare and on average smaller in size than the thousands of systems uncovered by the radio telescope.
“Giant jets were known before we started the campaign, but we had no idea that there would turn out to be so many,” says Martin Hardcastle, second author of the study and a professor of astrophysics at the University of Hertfordshire in England. “Usually when we get a new observational capability, such as LOFAR’s combination of wide field of view and very high sensitivity to extended structures, we find something new, but it was still very exciting to see so many of these objects emerging.”
Back in 2018, Oei and his colleagues began using LOFAR to study not black hole jets but the cosmic web of wispy filaments that crisscrosses the space between galaxies. As the team inspected the radio images for the faint filaments, they began to notice several strikingly long jet systems.
“When we first found the giant jets, we were quite surprised,” says Oei, who is also affiliated with Leiden Observatory in the Netherlands. “We had no idea that there were this many.”
To systematically search for more hidden jets, the team inspected the radio images by eye, used machine-learning tools to scan the images for signs of the looming jets, and enlisted the help of citizen scientists around the globe to eyeball the images further.
To find the galaxy from which Porphyrion originated, the team used the Giant Metrewave Radio Telescope(GMRT) in India along with ancillary data from a project called Dark Energy Spectroscopic Instrument(DESI), which operates from Kitt Peak National Observatory in Arizona. The observations pinpointed the home of the jets to a hefty galaxy about 10 times more massive than our Milky Way.
The team then used the W. M. Keck Observatory in Hawai’i to show that Porphyrion is 7.5 billion light-years from Earth. “Up until now, these giant jet systems appeared to be a phenomenon of the recent universe,” Oei says. “If distant jets like these can reach the scale of the cosmic web, then every place in the universe may have been affected by black hole activity at some point in cosmic time,” Oei says.
The observations from Keck also revealed that Porphyrion emerged from what is called a radiative-mode active black hole, as opposed to one that is in a jet-mode state. When supermassive black holes become active — in other words, when their immense forces of gravity tug on and heat up surrounding material — they are thought to either emit energy in the form of radiation or jets. Radiative-mode black holes were more common in the young, or distant, universe, while jet-mode ones are more common in the present-day universe.
The fact that Porphyrion came from a radiative-mode black hole came as a surprise because astronomers did not know this mode could produce such huge and powerful jets. What is more, because Porphyrion lies in the distant universe where radiative-mode black holes abound, the finding implies there may be a lot more colossal jets left to be found.
“We may be looking at the tip of the iceberg,” Oei says. “Our LOFAR survey only covered 15 percent of the sky. And most of these giant jets are likely difficult to spot, so we believe there are many more of these behemoths out there.”
How the jets can extend so far beyond their host galaxies without destabilizing is still unclear. “Martijn’s work has shown us that there isn’t anything particularly special about the environments of these giant sources that causes them to reach those large sizes,” says Hardcastle, who is an expert in the physics of black hole jets. “My interpretation is that we need an unusually long-lived and stable accretion event around the central, supermassive black hole to allow it to be active for so long — about a billion years — and to ensure that the jets keep pointing in the same direction over all of that time. What we’re learning from the large number of giants is that this must be a relatively common occurrence.”
As a next step, Oei wants to better understand how these megastructures influence their surroundings. The jets spread cosmic rays, heat, heavy atoms, and magnetic fields throughout the space between galaxies. Oei is specifically interested in finding out the extent to which giant jets spread magnetism.
“The magnetism on our planet allows life to thrive, so we want to understand how it came to be,” he says. “We know magnetism pervades the cosmic web, then makes its way into galaxies and stars, and eventually to planets, but the question is: Where does it start? Have these giant jets spread magnetism through the cosmos?”
Carousel Lens: A Well-modeled Strong Lens with Multiple Sources Spectroscopically Confirmed by VLT/MUSE
by William Sheu, Aleksandar Cikota, Xiaosheng Huang, Karl Glazebrook, Christopher Storfer, Shrihan Agarwal, David J. Schlegel, Nao Suzuki, Tania M. Barone, Fuyan Bian, Tesla Jeltema, Tucker Jones, Glenn G. Kacprzak, Jackson H. O’Donnell, Keerthi Vasan G. C. in The Astrophysical Journal
In a rare and extraordinary discovery, researchers have identified a unique configuration of galaxies that form the most exquisitely aligned gravitational lens found to date. The Carousel Lens is a massive cluster-scale gravitational lens system that will enable researchers to delve deeper into the mysteries of the cosmos, including dark matter and dark energy.
“This is an amazingly lucky ‘galactic line-up’ — a chance alignment of multiple galaxies across a line-of-sight spanning most of the observable universe,” said David Schlegel, a co-author of the study and a senior scientist in Berkeley Lab’s Physics Division. “Finding one such alignment is a needle in the haystack. Finding all of these is like eight needles precisely lined up inside that haystack.”
The Carousel Lens is an alignment consisting of one foreground galaxy cluster (the ‘lens’) and seven background galaxies spanning immense cosmic distances and seen through the gravitationally distorted space-time around the lens. In the dramatic image below:
- The lensing cluster, located 5 billion light years away from Earth, is shown by its four brightest and most massive galaxies (indicated by La, Lb, Lc, and Ld), and these constitute the foreground of the image.
- Seven unique galaxies (numbered 1 through 7), appear through the lens. These are located far beyond, at distances from 7.6 to 12 billion light years away from Earth, approaching the limit of the observable universe.
- Each galaxy’s repeated appearances (indicated by each number’s letter index, e.g., a through d) show differences in shape that are curved and stretched into multiple “fun house mirror” iterations caused by the warped space-time around the lens.
- Of particular interest is the discovery of an Einstein Cross — the largest known to date — shown in galaxy number 4’s multiple appearances (indicated by 4a, 4b, 4c, and 4d). This rare configuration of multiple images around the center of the lens is an indication of the symmetrical distribution of the lens’ mass (dominated by invisible dark matter) and plays a key role in the lens-modeling process.
Light traveling from far-distant space can be magnified and curved as it passes through the gravitationally distorted space-time of nearer galaxies or clusters of galaxies. In rare instances, a configuration of objects aligns nearly perfectly to form a strong gravitational lens. Using an abundance of new data from the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Surveys, recent observations from NASA’s Hubble Space Telescope, and the Perlmutter supercomputer at the National Energy Research Scientific Computing Center (NERSC), the research team built on their earlier studies (in May 2020 and Feb 2021) to identify likely strong lens candidates, laying the groundwork for the current discovery.
“Our team has been searching for strong lenses and modeling the most valuable systems,” explains Xiaosheng Huang, a study co-author and member of Berkeley Lab’s Supernova Cosmology Project, and a professor of physics and astronomy at the University of San Francisco. “The Carousel Lens is an incredible alignment of seven galaxies in five groupings that line up nearly perfectly behind the foreground cluster lens. As they appear through the lens, the multiple images of each of the background galaxies form approximately concentric circular patterns around the foreground lens, as in a carousel. It’s an unprecedented discovery, and the computational model generated shows a highly promising prospect for measuring the properties of the cosmos, including those of dark matter and dark energy.”
The study also involved several Berkeley Lab student researchers, including the lead author, William Sheu, an undergraduate student intern with DESI at the beginning of this study, now a PhD student at UCLA and a DESI collaborator.
The Carousel Lens will enable researchers to study dark energy and dark matter in entirely new ways based on the strength of the observational data and its computational model.
“This is an extremely unusual alignment, which by itself will provide a testbed for cosmological studies,” observes Nathalie Palanque-Delabrouille, director of Berkeley Lab’s Physics Division. “It also shows how the imaging done for DESI can be leveraged for other scientific applications,” such as investigating the mysteries of dark matter and the accelerating expansion of the universe, which is driven by dark energy.
JIRAM Observations of Volcanic Flux on Io: Distribution and Comparison to Tidal Heat Flow Models
by M. Pettine, S. Imbeah, J. Rathbun, A. Hayes, R. M. C. Lopes, A. Mura, F. Tosi, F. Zambon, S. Bertolino in Geophysical Research Letters
By staring into the hellish landscape of Jupiter’s moon Io — the most volcanically active location in the solar system — Cornell University astronomers have been able to study a fundamental process in planetary formation and evolution: tidal heating.
“Tidal heating plays an important role in the heating and orbital evolution of celestial bodies,” said Alex Hayes, professor of astronomy. “It provides the warmth necessary to form and sustain subsurface oceans in the moons around giant planets like Jupiter and Saturn.”
“Studying the inhospitable landscape of Io’s volcanoes actually inspires science to look for life,” said lead author Madeline Pettine, a doctoral student in astronomy.
By examining flyby data from the NASA spacecraft Juno, the astronomers found that Io has active volcanoes at its poles that may help to regulate tidal heating — which causes friction — in its magma interior.
“The gravity from Jupiter is incredibly strong,” Pettine said. “Considering the gravitational interactions with the large planet’s other moons, Io ends up getting bullied, constantly stretched and scrunched up. With that tidal deformation, it creates a lot of internal heat within the moon.”
Pettine found a surprising number of active volcanoes at Io’s poles, as opposed to the more-common equatorial regions. The interior liquid water oceans in the icy moons may be kept liquefied by tidal heating, Pettine said.
In the north, a cluster of four volcanoes — Asis, Zal, Tonatiuh, one unnamed and an independent one named Loki — were highly active and persistent with a long history of space mission and ground-based observations. A southern group, the volcanoes Kanehekili, Uta and Laki-Oi demonstrated strong activity. The long-lived quartet of northern volcanoes concurrently became bright and seemed to respond to one another. “They all got bright and then dim at a comparable pace,” Pettine said. “It’s interesting to see volcanoes and seeing how they respond to each other.
Stable carbon isotope evolution of formaldehyde on early Mars
by Shungo Koyama, Tatsuya Yoshida, Yoshihiro Furukawa, Naoki Terada, Yuichiro Ueno, Yuki Nakamura, Arihiro Kamada, Takeshi Kuroda, Ann Carine Vandaele in Scientific Reports
Although Mars is currently a cold, dry planet, geological evidence suggests that liquid water existed there around 3 to 4 billion years ago. Where there is water, there is usually life. In their quest to answer the burning question about life on Mars, researchers at Tohoku University created a detailed model of organic matter production in the ancient Martian atmosphere.
Organic matter refers to the remains of living things such as plants and animals, or the byproduct of certain chemical reactions. Whatever the case, the stable carbon isotope ratio (13C/12C) found in organic matter provides valuable clues about how these building blocks of life were originally formed, giving scientists a window into the past. As such, it has become a point of interest for Mars expeditions. For example, the Mars rover Curiosity (operated by NASA) revealed that organic matter found in sediments from that era on Mars are unusually depleted in 13C. It was also discovered that the carbon isotope ratios varied significantly between samples. However, the reason for this variability was a mystery.
To expand on these findings, a research group led by Shungo Koyama, Tatsuya Yoshida, and Naoki Terada from Tohoku University developed a Martian atmospheric evolution model. The model focused on formaldehyde (H2CO), which members of this research team previously determined could feasibly be produced in the ancient Martian atmosphere. The reason for this choice is that formaldehyde can generate complex organic compounds such as sugars, which are essential for life. In other words, formaldehyde may be the missing factor that could explain the anomalous values of the Curiosity rover samples. It could also be a sign of past life.
This model combined a photochemical model with a climate model to estimate the changes in the carbon isotope ratio of formaldehyde on Mars, dating back 3 to 4 billion years. It revealed that the depletion of 13C in formaldehyde is due to the photodissociation of CO2 by solar ultraviolet radiation, which results in the preference of one stable isotope over another. The study also showed that the carbon isotope ratio varied based on factors such as the atmospheric pressure on Mars at the time, the fraction of light reflected by the planet’s surface, the ratio of CO to CO2, and the amount of hydrogen released by volcanic activity.
“This model provides a possible explanation for previously unexplained findings, such as why 13C was mysteriously depleted.” remarks Koyama, a graduate student at Tohoku University.
This discovery indicates that formaldehyde contributed to the formation of organic matter on ancient Mars, implying that bio-important molecules such as sugars and ribose (a component of RNA, which is present in all living cells) may have been produced on the planet.
Subscribe to Paradigm!
Medium, Twitter, Telegram, Telegram Chat, LinkedIn, and Reddit.
Main sources
Research articles